Barbara E. Horn, of the Estate of Daniel Ray Horn, Deceased v. Thoratec Corporation

376 F.3d 163, 2004 U.S. App. LEXIS 14942, 2004 WL 1613556

• Court: Court of Appeals for the Third Circuit
• Decided: July 20, 2004
• Docket: 02-4597
• Status: Published

Opinions

GARTH, Circuit Judge.

Barbara Horn (“Horn”) appeals from the District Court’s grant of summary judgment to Thoratec Corp. (hereinafter “TCI” ¹), based on its determination that Horn’s claims against TCI are preempted by the express preemption provision in the Food Drug and Cosmetic Act (the “Act”), 21 U.S.C. § 360k(a).² We affirm.

I.

TCI manufactured and distributed the left ventricular assist device known as the HeartMate. The HeartMate is a pump that assists the blood flow between the heart’s ventricle and the aorta in patients with cardiac conditions. The inlet side tube is surgically attached to the heart via the ventricle, and carries blood from the heart into the pump. The outlet side tube brings blood from the pump to the aorta, where it is dispersed to the body. There is a tube attached to the pump that exits the body and connects to an external console. The console contains an air compressor which powers the HeartMate.

The facts underlying this case pertain to the outlet side tube, which connects the pump to the aorta. The connection between the pump and the tube, called the “elbow,” is inserted into an adapter conduit, which is screwed into the open port of the pump. A screw ring is secured over the elbow to ensure that it remains connected to the adapter conduit and the pump. A suture is tied over the screw ring and secured to the adapter conduit to ensure it will not rotate.³ The HeartMate was approved by the FDA pursuant to the Pre-Market Approval (“PMA”) process set forth at 21 U.S.C. § 360e(c) (discussed in depth, infra).

On January 17, 1998, Horn’s husband, Daniel Horn, was admitted to Williamsport Hospital suffering a heart attack. He was later transferred to Hershey Medical Center. Doctors there determined that Mr. Horn required a heart transplant, and they waited for a suitable donor heart to become available. On January 22, 1998, Mr. Horn’s condition deteriorated and a Heart-Mate was implanted in him to provide circulatory support. He was then transferred to an assisted living facility.

On May 3, 1998, Mr. Horn began to bleed from the spot where the HeartMate tube exited his body. Thereupon, he underwent exploratory surgery at Hershey Medical Center, during which Dr. Benjamin Sun discovered that the suture on Mr. Horn’s HeartMate had worn off and the screw ring linking the pump to the output side elbow had disconnected. The disconnection had allowed an air embolus to travel to Mr. Horn’s brain. Although Dr. Sun reconnected the screw ring and once again linked the pump to the elbow, it was too late. Mr. Horn suffered a brain hemorrhage, and he was rendered brain dead. On May 8, 1998, his organs were donated for transplant and he was pronounced dead.

On April 28, 2000, Horn filed a Complaint against TCI in the United States District Court for the Middle District of Pennsylvania. The Complaint alleged defective design and manufacture of the HeartMate and failure to warn of the alleged defects; it was based on Horn’s claim that the HeartMate’s output side elbow was defectively designed. TCI moved for summary judgment, arguing that Horn’s state law claims are expressly preempted by 21 U.S.C. § 360k(a).

The District Court granted TCI’s motion on November 7, 2002, holding that Horn’s state common law claims were preempted. The District Court applied a two-prong test endorsed by the Sixth and Eleventh Circuits,⁴ which instructs that a state claim attacking the safety of a medical device is preempted if (1) the FDA has established specific federal requirements that are applicable to that particular device, and (2) the state claim is different from, or in addition to, the specific federal requirements.

In granting TCI’s motion for summary judgment on express preemption grounds, the District Court found that (1) the HeartMate’s PMA approval process imposes a specific federal requirement applicable to the HeartMate, and (2) if Horn were successful on her state law claims, “any judgment that the HeartMate was unsafe or otherwise substandard would be in direct conflict [with]-i.e., different from-the FDA’s determination that the product was suitable for use.” Dist. Ct. Op. at 20. This timely appeal followed.

II.

We have jurisdiction to hear this appeal pursuant to 28 U.S.C. § 1291. Review of a district court’s decision to grant a motion for summary judgment is plenary. Goodman v. Mead Johnson & Co., 534 F.2d 566, 573 (3d Cir.1976), cert. denied, 429 U.S. 1038, 97 S.Ct. 732, 50 L.Ed.2d 748 (1977); Hilfirty v. Shipman, 91 F.3d 573, 577 (3d Cir.1996).

Summary judgment is appropriate only when there is no genuine issue as to any material fact and the moving party is entitled to a judgment as a matter of law. See Fed.R.Civ.P. 56(e); see also Armbruster v. Unisys Corp., 32 F.3d 768, 777 (3d Cir. 1994). In examining the record, the court gives the nonmoving party the benefit of all reasonable inferences from the record. Saldana v. Kmart Corp., 260 F.3d 228, 232 (3d Cir.2001); Gray v. York Newspapers, Inc., 957 F.2d 1070, 1078 (3d Cir.1992).

This Court also exercises plenary review over a district court’s preemption determination, as it is a question of law. Travitz v. Northeast Dep’t ILGWU Health & Welfare Fund, 13 F.3d 704, 708 (3d Cir.1994), cert. denied, 511 U.S. 1143, 114 S.Ct. 2165, 128 L.Ed.2d 888 (1994); Michael v. Shiley, Inc., 46 F.3d 1316, 1321-22 (3d Cir.1995).

III.

At issue is whether Horn’s suit against TCI, alleging causes of action under Pennsylvania common law, is expressly preempted. We need not examine the doctrine of implied preemption, because the Act under which the FDA preempted the state causes of action contains an express preemption clause, which obviates any reference to the doctrine of implied preemption. The express preemption clause, 21 U.S.C. § 360k(a), provides:

[N]o State or political subdivision of a State may establish or continue in effect with respect to a device intended for human use any requirement -

(1) which is different from, or in addition to, any requirement applicable under this chapter to the device, and

(2) which relates to the safety or effectiveness of the device or to any other matter included in a requirement applicable to the device under this chapter.

In this case, Horn contends that her state common law claims would impose generally applicable duties to use good care in manufacturing and to warn users of the product’s attendant risks. They would not, she argues, impose specific requirements with respect to the HeartMate. Paragraphs 15 and 16 of Horn’s Complaint set forth the gravamen of her action as follows:⁵

15.... The continual pumping action of the TCI HeartMate, together with natural body movements, caused the wearing away of the suture so placed, and once the suture was worn through, said movement of the pump caused the screw ring to become unscrewed.

16. Had the screw ring been of an appropriate and feasible design which would not permit the screw ring to become unscrewed as a result of pump movement, or had something more durable than a suture been used to secure the tightened screw ring, or had the threaded sleeve with the eyelet been placed in such a way that the retaining suture did not run across the interior portion of the screw ring directly beneath the underside of the sternum, the disconnection which ultimately caused Mr. Horn’s death would never have occurred.

TCI responds that Horn’s state common law claims would impose state requirements that are specifically applicable to the HeartMate, and as such are expressly preempted.

Horn relies on Medtronic v. Lohr, 518 U.S. 470, 116 S.Ct. 2240, 135 L.Ed.2d 700 (1996), a Supreme Court case which involved the FDA’s approval of a pacemaker. In that case, which we discuss in more detail later, the FDA’s approval of the device did not result in preemption of the plaintiff Lohr’s state law claims because the approval process involved in that case was not the same detailed approval process that was employed by the FDA to approve the HeartMate. In Lohr, the FDA determined that the pacemaker was “substantially- equivalent” to an existing FDA-approved device pursuant to § 510(k) of the Act, and therefore did not undergo the far more thorough and rigorous PMA approval process under § 360e(c) of the Act. It was this latter type of approval that the HeartMate received.

The FDA, in its Amicus Curiae Letter Brief to this Court, contrasted the § 510(k) “substantial equivalence” approval process with the § 360e(c) PMA process as follows:

A manufacturer can obtain an FDA finding of ‘substantial equivalence’ by submitting a pre-market notification to the agency in accordance with Section 510(k) of the [Act]. 21 U.S.C. § 360(k). A device found to be ‘substantially equivalent’ to a predicate device is said to be ‘cleared’ by FDA (as opposed to ‘approved’ by the agency under a PMA). A pre-market notification submitted under Section 510(h) is thus entirely different from a PMA, which must include data sufficient to demonstrate to FDA that the device is safe and effective. See Lohr, 518 U.S. at 478-79, 116 S.Ct. 2240 (“The § 510(k) notification process is by no means comparable to the PMA process.”).

The number of medical devices that receive PMA review each year is dwarfed by the number of those that are marketed pursuant to cleared Section 510(k). In fiscal year 2003, for example, original PMAs represented only 54 of the 9,872 major submissions received. The previous fiscal year, original PMAs accounted for 49 of 10,323 total submissions.⁶

As it concerns the HeartMate, TCI contends that because it received FDA approval of the HeartMate through the PMA process, and not under the “substantial equivalence” clearance standard of § 510(k), and because Horn’s reading and analysis of the “specificity” of the state law requirement in Lohr is flawed, the Lohr decision is not controlling. We agree.

IV.

This Court has addressed the issue of the Act’s express preemption before, and those decisions guide us here. In Gile v. Optical Radiation Corp., 22 F.3d 540, 541 (3d Cir.), cert. denied, 513 U.S. 965, 115 S.Ct. 429, 130 L.Ed.2d 342 (1994), the plaintiff brought a state common law products liability and negligence action against an intraocular lens manufacturer. We determined in Gile that state common law claims may impose state “requirements,” as that term is used in § 360k(a) of the Act, and that the state law requirements were preempted by the FDA. Id. at 541-42.

Thereafter, in Michael v. Shiley, Inc., 46 F.3d 1316 (3d Cir.1995), the recipient of a heart valve brought an action against the heart valve manufacturer for negligent manufacture and design, strict products liability, breach of implied warranty of merchantability and fitness for a particular purpose, breach of express warranty, and fraud on the FDA. Id. at 1321. The heart valve manufacturer argued that the Act preempted all of the plaintiffs claims. Id. at 1322. On the issue of preemption, we stated that:

[SJection [360k(a) ] pre-empts only state imposed requirements. Further, it preempts those requirements only when they differ from or add to a previously established FDA requirement and relate to the safety or efficacy of the regulated device. When a state law differs from or adds to an FDA requirement and when a state law relates to the safety or effectiveness of a device approved by the FDA, the state law is pre-empted. Conversely, when a state law neither imposes requirements nor differs from or adds to an FDA requirement nor relates to the safety or effectiveness of the device or to any other matter included in an FDA requirement, the state law is not pre-empted by § 360k.

Id. at 1323. We concluded that Michael’s claims for negligence, strict liability, breach of implied warranties, and fraud on the FDA were preempted. Id. at 1325-31.⁷ Most significantly, we held that the PMA process, as well as the labeling and “good manufacturing” requirements to which the heart valve was subjected, constituted proper bases for preemption under § 360k(a). Id. at 1324.

The following year, the Supreme Court decided Medtronic v. Lohr, 518 U.S. 470, 116 S.Ct. 2240, 135 L.Ed.2d 700 (1996). In that case, to which we referred earlier, the plaintiff asserted common law negligence and strict liability claims and state law defective manufacture and mislabeling claims against the manufacturer of a pacemaker that was given FDA clearance under the § 510(k) “substantial equivalence” process. Lohr’s complaint stemmed from a defective lead in her pacemaker.

A plurality of the Lohr Court held that Lohr’s claims against the manufacturer of the § 510(k)-approved pacemaker were not preempted. Key to this holding was the plurality’s opinion that the § 510(k) process does not impose any federal “requirement” applicable to the device, but is rather a “generic federal standard.” Lohr, 518 U.S. at 486-87, 116 S.Ct. 2240. The Lohr Court did not consider whether the more rigorous PMA process under § 360e(c)-as distinct from the § 510(k) process-constitutes “a specific federal regulation of the product”⁸ (in this case the HeartMate), which, in turn, imposes strict FDA requirements upon the manufacturer.⁹

1. The Federal Requirement

A. General Analysis of the Federal Requirement

The primary element distinguishing Lohr from the instant case is the fact that the HeartMate received FDA approval through the rigorous § 360e(c) PMA process, not through the § 510(k) “substantial equivalence” process. The Lohr decision did not address the issue of whether the PMA process imposed federal requirements under § 360k(a). It suggested, however, that the analysis would have been significantly different if the device at issue in Lohr had weathered a more exacting federal investigation, such as the PMA process. Lohr, 518 U.S. at 501, 116 S.Ct. 2240. Indeed, the Lohr plurality distinguished the case from “a case in which the Federal Government has weighed the competing interests relevant to the particular requirement in question, reached an unambiguous conclusion about how those competing considerations should be resolved in a particular case or set of cases, and implemented that conclusion via a specific mandate on manufacturers or producers.” Id.

Furthermore, in response to the pacemaker manufacturer’s argument that Lohr’s state common law claims were preempted by the FDA’s “good manufacturing practices” regulations, 21 C.F.R. §§ 820.20-820.198 (1995), and by the FDA labeling regulations requiring devices to carry warnings, 21 C.F.R. § 801.109 (1995), the Lohr plurality stated:

the federal requirements [imposed under § 510(k) ] reflect important but entirely generic concerns about device regulation generally, not the sort of concerns regarding a specific device or field of device regulation that the statute or regulations were designed to protect from potentially contradictory state requirements.

518 U.S. at 501, 116 S.Ct. 2240.

We hold that the requirements imposed by the FDA upon the HeartMate when it was granted PMA approval are precisely “the sort of concerns regarding a specific device” which the Supreme Court intimated would give rise to preemption under § 360k(a). This portion of our decision in Michael v. Shiley, Inc., 46 F.3d at 1324, remains unchanged by the Lohr decision.¹⁰

In this ease, the HeartMate’s PMA process began in 1975 when its basic design was completed. In 1985, after ten years of live animal and human cadaver studies, the HeartMate was granted an investigational device exemption (“IDE”) by the FDA in order to begin clinical trials. Over the next seven years, clinical trials of the HeartMate were conducted at various hos-pitáis. During this period, TCI submitted more than ninety supplements to the FDA, and the FDA made numerous inquiries about the HeartMate and its clinical trials, including correspondence concerning a leak from the HeartMate’s screw ring and approval of subsequent design changes (i.e., the addition of the bonding agent and suture). In 1992, TCI submitted its PMA application to the FDA, and supplemented it in the ensuing three years with a substantial amount of amendments and responses to FDA questions. In 1994, after extensive review of TCI’s application, the FDA approved the HeartMate for commercial sale in the form specified in the application.

There is no doubt that, as a practical reality, the PMA process imposed requirements that were specifically applicable to the HeartMate, and that triggered preemption under § 360k(a). It imposed mandatory conditions - created through a decades-long process of correspondence, clinical testing and device alteration - pertaining to the HeartMate’s manufacturing, packaging, storage, labeling, distribution and advertising. See 21 C.F.R. §§ 814.39, 814.80 (setting forth requirement that PMA approval be obtained before device may be manufactured or marketed, and method for supplementing PMA application). Other Courts of Appeal have held that PMA approval by the FDA constitutes approval of the product’s design, testing, intended use, manufacturing methods, performance standards and labeling that is specific to the product. See Brooks v. Howmedica, Inc., 273 F.3d 785, 795-96 (8th Cir.2001); Kemp v. Medtronic, Inc., 231 F.3d 216, 226-27 (6th Cir.2000); Mitchell v. Collagen Corp., 126 F.3d 902, 913 (7th Cir.1997). But see Goodlin v. Medtronic, Inc. 167 F.3d 1367, 1377 (11th Cir.1999).¹¹

B. The FDA’s Position¹²

While we acknowledge that the FDA’s interpretation of statutes that it has been charged by Congress with enforcing is not fully dispositive of the issues here, the Supreme Court has instructed us that the FDA’s preemption determinations are significant and should inform our interpretation of § 360k(a). Indeed, the Supreme Court’s decision in Lohr was “substantially informed” by the FDA, in the context of § 510(k). Lohr, 518 U.S. at 495, 116 S.Ct. 2240. Hence, we have no hesitation in looking to the FDA for its interpretation of § 360k(a) in the medical device context. Lohr stated:

The FDA regulations interpreting the scope of § 360k’s pre-emptive effect support the Lohrs’ view, and our interpretation of the pre-emption statute is substantially informed by those regulations ... Congress has given the FDA a unique role in determining the scope of § 360k’s pre-emptive effect ... [I]n most cases a state law will be pre-empt-ed only to the extent that the FDA has promulgated a relevant federal ‘requirement.’ Because the FDA is the federal agency to which Congress has delegated its authority to implement the provisions of the Act, the agency is uniquely qualified to determine whether a particular form of state law stands as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress, and, therefore, whether it should be pre-empted.

Lohr, 518 U.S. at 495-96, 116 S.Ct. 2240 (internal citations and quotations omitted).

Horn, in her brief before us, relied heavily on an FDA amicus curiae submission filed with the Supreme Court in opposition to certiorari in Smiths Industries Medical Systems, Inc. v. Kernats, 522 U.S. 1044, 118 S.Ct. 684, 139 L.Ed.2d 631 (1998). However, those views have been expressly disclaimed and rejected by the FDA in its Amicus Curiae Letter Brief to this Court. In its current brief, the FDA has unequivocally expressed the opinion that state common law claims such as those made by Horn against a PMA-approved device are preempted. With great particularity, the FDA specifically addressed the HeartMate and concluded that because the device was the subject of PMA approval under § 360e(c), and not the subject of “substantial equivalence” clearance under § 510(k), the state law claims asserted by Horn are preempted.¹³

The FDA, when PMA approval is granted, imposes federal requirements based on the highly detailed and prescriptive nature of the PMA process and the approval order that results from it. In its Amicus Curiae Letter Brief at pages 23-24, the FDA writes:

FDA can impose requirements by rule or order, regardless of whether or not the requirements were initially suggested to the agency by an outside party.... Although the PMA approval order does not itself expressly reiterate all of the specific features the device’s design, labeling, and manufacturing processes must have, it specifically approves as a matter of lav) those features set forth in the application and binds the manufacturer to produce and market the product in compliance with the specifications as approved by FDA

(emphasis added).

The FDA also clearly distinguished the PMA process from the § 510(k) substantial equivalence process, which was the subject of the Supreme Court’s decision in Lohr, writing:

Unlike a section 510(k) clearance, which only determines whether two products are substantially equivalent, PMA approval consummates an exhaustive inquiry into the risks and efficacy of a device....

In Lohr, not surprisingly, the Court premised its holding against preemption on the fact that the device had been cleared only through the Section 510(k) process, a “limited form of review.” Lohr, 518 U.S. at 478, 116 S.Ct. 2240. A manufacturer may change the design and labeling of a Section 510(k)-cleared device as long as it continues to be substantially equivalent to its predicate. 21 C.F.R. § 807.81. In direct contrast to the PMA regime, FDA does not ‘approve’ changes to a Section 510(k)~ cleared device. Rather, the manufacturer simply has to demonstrate that its device is still substantially equivalent to its predicate. Moreover, the range of changes that a manufacturer can make to a [§ 510(k) ] cleared device without getting prior authority from FDA is broader than for a[PMA] approved device. A manufacturer of a cleared device must submit a Section 510(k) notice to FDA only for changes that ‘could significantly affect safety or effectiveness of the device,’ or that represent a ‘major change’ in the intended use of the device. 21 C.F.R. § 807.81.

... For [PMA devices], after a very lengthy process involving thousands of pages of documentation and many hours of expert analysis, and often including substantial give-and-take between the agency and the manufacturer, FDA approves a new device, including detailed specifications for its design, manufacture, performance, labeling, and use. Any of these specifications may be changed in [a] way that affects safety and effectiveness only with FDA’s authorization.

Id. at 20-21 (emphasis added).

The dissent, in discussing Lohr v. Med-tronic (see Dissenting Op. at 180), has ignored the very salient fact that Lohr was a § 510k “substantial equivalence” decision and not, as this case is, a § 360e(c) PMA case. We have discussed the dramatic difference between these two approval processes in both Sections III and IV of this opinion. We have emphasized that the PMA approval process mandates that the manufacturer (in this case, TCI) produce and market the HeartMate in compliance, and only in compliance, with the requirements and specifications approved by the FDA. This is a far cry from the § 510k process which was the subject of Lohr, and which notably the Lohr Court held was “by no means comparable to the PMA process.” Lohr, 518 U.S. at 478-79, 116 S.Ct. 2240.

This significant distinction is understandably absent from the dissent’s discussion because, as we point out in this opinion, any effort by Horn to prove her general common law claims of negligence, labeling or deficient design would necessarily differ from, or add to, the design, manufacturing or labeling approved and pre-empted by the FDA. See 21 U.S.C. § 360k(a); 21 C.F.R. § 808.1(b) (see p. 174, infra, for text of regulation); Kemp v. Medtronic, Inc., 231 F.3d 216 (6th Cir. 2000); Mitchell v. Collagen Corp., 126 F.3d 902 (7th Cir.1997), Papike v. Tambrands, Inc., 107 F.3d 737 (9th Cir.1997), and Michael v. Shiley, Inc., 46 F.3d 1316, 1323 (3d Cir.1995).

Thus, the District Court’s position, the FDA’s position, and our position are all in accord: the FDA’s PMA approval of the HeartMate imposed specific federal requirements upon the HeartMate under § 360k(a) which, as we explain infra, preempts Horn’s state common law claims. Cf. Hawkins v. Leslie’s Pool Mart, Inc., 184 F.3d 244, 250-51 (3d Cir.1999) (holding that labeling claims were preempted by similar preemption clause in Federal Insecticide, Fungicide and Rodenticide Act because, in contrast to § 510(k) approval, the EPA had incorporated specific labeling requirements that could not be changed without pre-approval).

2. The State Requirement

A. General Analysis of the State Requirement

The remaining issue is whether Horn’s state common-law claims constitute state requirements with respect to the Heart-Mate which are different from, or in addition to, the federal requirements. See 21 U.S.C. § 360k(a). As we noted earlier, it is firmly established that a “requirement” under § 360k(a) can include legal requirements that arise out of state common-law damages actions. See Gile, 22 F.3d at 541-42. Consequently, the only matter that we must resolve is whether § 360k(a) preempts the particular state common law claims brought by Horn.

The only state requirements asserted by Horn are general requirements stemming from state common law: the HeartMate was designed in a defective manner, it was manufactured in a defective manner, and the manufacturer had failed to warn of the alleged defects. The thrust of Horn’s Complaint was that had the screw ring been of a better and more feasible design and had something more durable than a suture been used or had the threaded sleeve with the eyelet been placed differently in Mr. Horn’s body, his death would not have resulted.¹⁴

Horn has never claimed that Pennsylvania has established a requirement of specific device content pertaining to the HeartMate.¹⁵ She has never alleged that Pennsylvania requires all sutures for the HeartMate to be fabricated from a substance different than the suture which the FDA has approved. Nor has she ever alleged that there are specific requirements mandated by the Commonwealth of Pennsylvania as to how a medical device such as the HeartMate must be fabricated or designed or implanted within the patient’s body. Indeed, if Horn had alleged any “requirement” similar to these it would have been fatal to her claims, because each of them would have either been in addition to, or different from, the federal requirements imposed through the FDA’s PMA approval of the HeartMate.

In the absence of any specific device requirements,¹⁶ we are left with Horn’s general common law claims of negligence, defective design, etc. The question that remains is: can Horn’s common law “general” claims, which are not specific “with respect to” the HeartMate, constitute “requirements” that survive preemption under § 360k(a)?

Our analysis begins, as it must, with the Lohr decision. Both Horn and TCI, as well as the authorities that have considered FDA preemption under § 360k(a), have understandably read Medtronic v. Lohr as a starting point for interpreting § 360k(a) and the FDA’s regulations at 21 C.F.R. § 808.1(d).¹⁷ They have also considered the impact upon the FDA’s PMA approval of a medical device when general state tort law claims alleging negligence, design defects, failure to warn, and the like, are filed against the manufacturer of the device. See, e.g., Martin v. Medtronic, 254 F.3d 573 (5th Cir.2001).

In Lohr, the plaintiff sued Medtronic for negligent manufacture and failure to warn, essentially the same claims Horn has brought against TCI. The four-judge plurality in Lohr concluded that those claims “escape[d] pre-emption, not because the source of the duty is a judge-made common-law rule, but rather because their generality leaves them outside the category of requirements that § 360k envisioned to be ‘with respect to’ specific devices such as pacemakers.” Lohr, 518 U.S. at 502, 116 S.Ct. 2240.

Although Justice Breyer joined in the section of the plurality’s opinion in which that statement appeared, he wrote separately to emphasize that, unlike the plurality, he was “not convinced that future incidents of [§ 360k(a) ] preemption of common-law claims will be ‘few’ or ‘rare.’ ” Id. at 508, 116 S.Ct. 2240 (Breyer, J., concurring in part). As we read Justice Breyer’s concurring opinion, a state common law claim need not be developed specifically “with respect to” a particular medical device in order to be preempted. It would make little sense for Justice Breyer to write separately to emphasize that duties arising under state law can regularly lead to preemption, but simultaneously agree with the plurality that tort duties are almost always too general to warrant preemption. See Papike v. Tambrands, Inc., 107 F.3d 737, 742 (9th Cir. 1997). The more logical reading of Justice Breyer’s concurring opinion is that a court should carefully examine the state common law claim in order to determine whether that claim would impose a substantive requirement that conflicts with, or adds a greater burden to, a specific federal requirement. See Mitchell v. Collagen Corp., 126 F.3d 902, 911-12 (7th Cir.1997); Kemp v. Medtronic, 231 F.3d 216, 230 (6th Cir.2000); Martin v. Medtronic, 254 F.3d 573, 581-83 (5th Cir. 2001).

The dissent cites to Alexander v. Sandoval, 532 U.S. 275, 285 n. 5, 121 S.Ct. 1511, 149 L.Ed.2d 517 (2001), for the proposition that the lower federal courts do not give “much precedential weight” to a concurring opinion of the United States Supreme Court, even where the concurring opinion is compatible with the majority opinion. See Dissenting Op. at 184. We disagree, as this principle has no application to this case. Sandoval bears little resemblance to the situation in Lohr. In Sandoval, Justice Scalia merely observed that the opinion of a three-member concurrence in Lau v. Nichols, 414 U.S. 563, 94 S.Ct. 786, 39 L.Ed.2d 1 (1974), was not binding precedent on an issue that the five-member majority in Lau did not reach. In Lohr, by contrast, Justice Breyer cast the so-called “swing vote,” which was crucial to the outcome of the case and without which there could be no majority. Moreover, Justice Breyer did not discuss issues in his concurring opinion that Justice Stevens, writing on behalf of the four-judge plurality, did not reach.

Splintered opinions by the Supreme Court often result in some confusion as to which opinion or rationale is binding on the lower federal courts. In an attempt to provide some guidance in such situations, the Supreme Court has instructed that the lower courts should follow the rationale “taken by those Members who concurred in the judgments on the narrowest grounds.” Gregg v. Georgia, 428 U.S. 153, 169 n. 15, 96 S.Ct. 2909, 49 L.Ed.2d 859 (1976) (plurality opinion); see also Marks v. United States, 430 U.S. 188, 192-93, 97 S.Ct. 990, 51 L.Ed.2d 260 (1977) (stating that, “[wjhen a fragmented Court decides a case and no single rationale explaining the result enjoys the assent of five Justices, ‘the holding of the Court may be viewed as that position taken by those Members who concurred in the judgments on the narrowest grounds.... ’ ”); Planned Parenthood of Southeastern Pa. v. Casey, 947 F.2d 682, 693 (3d Cir.1991) (discussing in detail the “narrowest ground” principle), modified on other grounds, 505 U.S. 833, 112 S.Ct. 2791, 120 L.Ed.2d 674 (1992).

If the “narrowest ground” approach is applied to Lohr, Justice Breyer’s opinion takes on added significance. Whereas Justice Stevens concluded that “ § 360(k) simply was not intended to preempt most, let alone all, general common-law duties enforced by damages actions,” see Lohr, 518 U.S. at 491, 116 S.Ct. 2240, Justice Breyer concluded that “ordinarily, insofar as the [FDA] pre-empts a state requirement embodied in a state statute, rule, regulation, or other administrative action, it would also pre-empt a similar requirement that takes the form of a standard of care or behavior imposed by a state-law tort action.” Id. at 504-05, 116 S.Ct. 2240 (Breyer, J., concurring in part and dissenting in part). Thus, Justice Breyer’s rationale is the more narrow of the two because, although the Lohrs’ claims were not preempted by § 360k(a), he was not prepared to join in Justice Stevens’ sweeping pronouncement that § 360k almost never preempts a state common law claim.

Of course, the splintered decision in Lohr is unique because Justice Breyer joined in some parts of Justice Stevens’ plurality opinion (thus making it a majority opinion at times), but did not join in other parts. Our dissenting colleague emphasizes that Justice Breyer joined in Part V of the plurality opinion, in which Justice Stevens concluded that the Lohrs’ common-law claims did not constitute specific state requirements because they were not “specifically developed ‘with respect to’ medical devices.” Lohr, 518 U.S. at 501, 116 S.Ct. 2240. This was not a principle that received Justice Breyer’s agreement. In his concurring opinion, Justice Breyer states that he must address two issues: (1) whether the FDA can “ever pre-empt a state-law tort action;” and (2) if so, whether the FDA pre-empts the claims brought by Lohr. Id. at 503, 116 S.Ct. 2240 (Breyer, J., concurring in part and dissenting in part).

In response to the first question, Justice Breyer expressly states that he “basically agreefd]” with Justice O’Connor’s discussion of that point in her dissenting opinion. Justice O’Connor concluded that “a fair reading of [§ 360k(a) ] indicates that state common-law claims are pre-empted, as the statute itself states, to the extent that their recognition would impose ‘any requirement’ different from, or in addition to, FDCA requirements applicable to the device.” Id. at 512, 116 S.Ct. 2240 (O’Con-nor, J., dissenting). Interestingly, Justice O’Connor also observed that “[t]he statute itself makes no mention of a requirement of specificity, and there is no sound basis for determining that such a restriction on ‘any requirement’ exists.” Id.

Thus, on the state requirement issue, Justice Breyer joined with the four-member dissent to make a majority.¹⁸ It seems that he merely parted ways with Justice O’Connor when it came time to apply that rationale to the state common-law claims (in a § 510(k) context) before the Court.

Although in Lohr the plurality opinion did not inform us of when common law requirements may become substantive requirements, we are satisfied that Horn’s general state law claims¹⁹ would impose substantive requirements on TCI that would conflict with, or add to, the requirements imposed by the FDA involved in the design, manufacturing, fabrication and labeling of the HeartMate. For example, Horn’s Complaint alleges that the Heart-Mate was negligently designed such that the screw ring could come unscrewed in spite of the presence of the suture. This claim unquestionably would require TCI to alter the HeartMate’s design by using either a different suture or screw ring. Yet the HeartMate’s design as approved by the FDA would remain approved by the FDA for national distribution and sale, and any changes to the design would require further FDA review and approval.²⁰

As TCI has pointed out in its brief, “[Horn’s] design defect claims ... would require TCI either to use an entirely different design than the screw ring to connect the outlet elbow to the pump, or to use different materials instead of a suture, or to place the eyelet in a different position. Similarly, her failure-to-warn claims would require TCI to provide different warnings and instructions from those approved by the FDA.” TCI Br. at 45. TCI is prohibited, however, by the FDA’s PMA approval order from making any such changes. See 21 C.F.R. 814.80.²¹

Because these state common law claims and duties are in severe tension with § 360k(a) in that they are either in addition to, or different from, the federal requirements established by the FDA in approving the HeartMate, they are necessarily preempted by federally imposed PMA requirements under § 360k(a).²² See, e.g., Kemp, 231 F.3d at 228-37; Mitchell, 126 F.3d at 911-15, Papike, 107 F.3d at 741-42.

B. The FDA’s Position

Our preemption conclusion is reinforced by the informed analysis found in the FDA’s amicus curiae brief. The FDA has clearly expressed its view that PMA approval in this particular case requires preemption. The FDA conceives of Horn’s state common law claims as imposing a “requirement” which is “different” from that imposed by the FDA in the PMA process, and thus requiring preemption. In its Amicus Curiae Letter Brief,²³ the FDA wrote:

... Here, plaintiff seeks to impose liability based on asserted flaws in the design, labeling and manufacture of the HeartMate as approved by FDA despite the fact that it complied with FDA requirements. Thus, plaintiff does attempt to impose a requirement different from [the requirement imposed by] FDA

There is no allegation that the Heart-Mate’s design, labeling, or methods of manufacture deviated from those set forth in the PMA approved by FDA. Accordingly, any finding of liability based upon TCPs failure to satisfy a standard different from those approved by FDA in the PMA process would necessarily rest upon an implicit requirement that this device be designed, manufactured or marketed in a way that differs from the way approved by FDA.

With respect to the impact of state common law tort claims on the federal regulatory framework for medical devices, the FDA wrote:

State common law tort actions threaten the statutory framework for the regulation of medical devices, particularly with regard to FDA’s review and approval of product labeling. State actions are not characterized by centralized expert evaluation of device regulatory issues. Instead, they encourage, and in fact require, lay judges and juries to second-guess the balancing of benefits and risks of a specific device to their intended patient population - the central role of FDA - sometimes on behalf of a single individual or group of individuals. That individualized redetermination of the benefits and risks of a product can result in relief - including the threat of significant damage awards or penalties - that creates pressure on manufacturers to add warnings that FDA has neither approved, nor found to be scientifically required, or withdrawal of FDA-approved products from the market in conflict with the agency’s expert determination that such products are safe and effective. This situation can harm the public health by retarding research and development and by encouraging ‘defensive labeling’ by manufacturers to avoid state liability, resulting in scientifically unsubstantiated warnings and underuti-lization of beneficial treatments.

Id. at 25-26.²⁴

The FDA’s views in its Amicus Curiae Letter Brief in this case echo the opinion it has voiced in another recent case. In a brief submitted to the Circuit Court of Tennessee in Murphree v. Pacesetter, Inc., et al., the FDA expressed concerns about the consequences of not preempting state common law claims such as Horn’s:

[I]t is inappropriate for a jury to second-guess FDA’s scientific judgment on such a matter that is within FDA’s particular expertise. FDA determines the scope of a device, including the components it comprises, and the appropriate regulatory pathway for the device.... FDA subsequently determines whether the device meets the PMA approval standard. The agency makes a reasoned and deliberate decision as to the correct pathway of regulation and whether to approve the device. Juries lack the scientific knowledge and technical expertise necessary to make such judgments....

[T]he prospect of hundreds of individual juries determining the propriety of particular device approvals, or the appropriate standards to apply to those approvals, is the antithesis of the orderly scheme Congress put in place and charged the FDA with implementing.

Such uncertainty as to the status of medical devices would create chaos for both the regulated industry and FDA.

Statement of Interest of the United States of America at 7-9, Murphree v. Pacesetter, Inc. et al, No. 005429-00-3 (Tenn. Circuit Ct. Dec. 12, 2003).

As we discussed earlier, a majority of the Court in Lohr emphasized that the FDA is “uniquely qualified” to determine whether a particular form of state law ... should be pre-empted” by § 360k. Lohr, 518 U.S. at 496, 116 S.Ct. 2240. Horn contends, however, that we should give no weight to the FDA’s interpretation because the FDA previously argued that PMA approval did not support preemption, and in any event, the FDA’s interpretation is entitled only to “near indifference.” See Dissenting Op. fn. 2 and Maj. Op. fn. 12, supra. We cannot agree that the FDA’s position is entitled to no deference, or “near indifference” simply because it represents a departure from its prior position. In Chevron U.S.A. Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 863-64, 104 S.Ct. 2778, 81 L.Ed.2d 694 (1984), the Supreme Court held that a revised interpretation by an agency is entitled to deference because “[a]n initial agency interpretation is not instantly carved in stone.” Accordingly, an agency may change its course so long as it can justify its change with a “reasoned analysis,” see Motor Vehicle Mfrs. Ass’n v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 42, 103 S.Ct. 2856, 77 L.Ed.2d 443 (1983), and we are fully persuaded that this standard has been met.²⁵

V.

Horn has not asserted that TCI has in any way failed to conform with the FDA requirements prescribed by its PMA-nor that it deviated from, or violated, any of the FDA’s federal statutes or regulations. Because the design of the HeartMate, the labeling and the instructions for its use, and the specification of the suture and its location when the HeartMate is implanted, as well as the other requirements imposed by the PMA, were the subject of extensive consideration by the FDA leading up to its PMA approval, any finding in Horn’s favor based on her general claims of negligence or defective desigp and manufacture-be it by a jury or a court-would necessarily amount to a state substantive requirement “different from, or in addition to, the federal requirements imposed by the FDA.” Any such finding would “stand as an obstacle to the accomplishment and execution of’ the objective of the safety and effectiveness of the HeartMate specifically and would conflict with the federal requirements imposed by the PMA. Geier v. American Honda Motor Co., 529 U.S. 861, 873, 120 S.Ct. 1913, 146 L.Ed.2d 914 (2000).

If, as we hold, the FDA’s express preemption clause found at 21 U.S.C. § 360k(a) pre-empts Horn’s state law claims, then there is no point in discussing “implied preemption,” a doctrine which our dissenting colleague addressed at length in an attempt to bolster his conclusion that Lohr, a § 510(k) opinion, governs this case. See Cipollone v. Liggett Group, Inc., 505 U.S. 504, 112 S.Ct. 2608, 120 L.Ed.2d 407 (1992) (“When Congress has considered the issue of pre-emption and has included in the enacted legislation a provision explicitly addressing that issue, and when that provision provides a reliable indicium of congressional intent with respect to state authority, there is no need to infer congressional intent to pre-empt state laws from the substantive provisions of the legislation.”) (citations and internal quotations omitted). We therefore do not address the dissent’s arguments predicated on “implied preemption.”

As a consequence we, together with our sister Courts of Appeal who have read Lohr in the same fashion as we have,²⁶ and together with the FDA’s current position, hold that Horn’s claims are preempted by § 360k(a). We will affirm the judgment of the District Court granting summary judgment to TCI.

1 . Thoratec Corporation, formerly known as Thermo Cardiosystems, Inc., is referred to by the parties and the District Court Judge as TCI. Therefore, we will also refer to defendant-appellee as TCI.

2 . The Medical Device Amendments to the Act allow the Food and Drug Administration ("FDA”) to regulate medical devices. See 21 U.S.C. §§ 360c et seq. For ease of reference throughout this opinion, we refer to the Act as the source of preemption.

3 .The HeartMate arrives at the surgeon pre-assembled. The surgeon need not manipulate the screw ring or suture when he implants the HeartMate.

4 . See Kemp v. Medtronic, Inc., 231 F.3d 216, 224-25 (6th Cir.2000); Goodlin v. Medtronic, Inc., 167 F.3d 1367, 1371 (11th Cir.1999).

5 . The FDA has summarized Horn's claims in the following manner:

[P]laintiff makes two main claims: first, that TCI should have employed a [suture] design to prevent the screw rings used to hold the device in place inside the patient's chest from becoming disconnected (plaintiff asserted that TCI overlooked better alternatives to the design it chose); [and] second, that TCI should have issued warnings to doctors, through either revisions in the product labeling or correspondence to health care professionals (commonly called "Dear Doctor letters”), against using the device if the suture as placed in the device packaging would face the patient's sternum.

FDA Amicus Curiae Letter Br. at 4-5.

6 . FDA Amicus Curiae Letter Br. at 12 (emphasis added).

7 . Michael’s claims for breach of express warranty (based on the heart valve’s packaging materials) and fraud (based on the manufacturer's advertisements and promotional materials), neither of which were the subject of the FDA’s PMA approval, were held not to be preempted because those claims arising out of private representations-as distinct from state requirements-were merely state-enforced common law remedies, and not state-imposed common law remedies. 46 F.3d at 1325-31.

8 . Mitchell v. Collagen Corp., 126 F.3d 902, 911 (7th Cir. 1997).

9 . Most circuits have followed Justice Breyer's concurrence in Lohr, which suggests that § 360k(a) preempts some, but not all, common law claims. 518 U.S. at 506, 116 S.Ct. 2240 (Breyer, J., concurring); see, e.g., Martin v. Medtronic, 254 F.3d 573 (5th Cir.2001); Brooks v. Howmedica, Inc., 273 F.3d 785 (8th Cir.2001); Kemp v. Medtronic, Inc., 231 F.3d 216 (6th Cir.2000); Mitchell v. Collagen Corp., 126 F.3d 902 (7th Cir.1997). Where the federal requirement at issue is specifically applicable to a particular device, Justice Breyer concluded, any state common law claim implicating that device is preempted. Id. at 505, 116 S.Ct. 2240. Justice Breyer concurred with the plurality’s decision that a common law claim against a § 510(k)-ap-proved device is not preempted, because § 510(k) does not impose a federal requirement that is specifically applicable to a particular device.

10 . In re Orthopedic Bone Screw Prods. Liab. Litig., 159 F.3d 817, 825 (3d Cir. 1998), is not to the contrary. Orthopedic, a § 501(k) case, in dealing with the alternate holding of Michael respecting the claim of fraud on the FDA, concluded that Lohr had overruled the alternate holding without affecting the preemption determination or any other holdings of the Michael opinion. This aspect of Orthopedic came into question when the Supreme Court in Buckman Co. v. Plaintiffs' Legal Comm., 531 U.S. 341, 121 S.Ct. 1012, 148 L.Ed.2d 854 (2001), held that a fraud on the FDA claim brought as a state cause of action was impliedly preempted without expressing any view on whether such a claim was expressly preempted by § 360k(a). See id. at 348 n. 2, 121 S.Ct. 1012.

See also Martin v. Medtronic, 254 F.3d 573, 583 (5th Cir.2001), which held that Lohr did not overrule the Fifth Circuit’s prior precedent established in Stamps v. Collagen Corp., 984 F.2d 1416 (5th Cir.1993), and that the state law claims asserted in Martin were preempted.

11 . The Eleventh Circuit was alone among the Courts of Appeals when it ruled in Goodlin that § 360k(a) does not preempt common law claims involving PMA-approved devices. Goodlin, 167 F.3d at 1368. The Tenth Circuit has ruled that the Act did not preempt a plaintiff’s common law tort claim against a medical device manufacturer, but the device at issue in that case did not undergo the § 360e(c) PMA analysis, but rather underwent the far less rigorous Investigative Device Exception (IDE) process. Oja v. Howmedica, 111 F.3d 782 (10th Cir.1997).

12 . The dissent in its footnote 2 argues that the FDA's position on preemption is entitled only to "near indifference,” thereby contending that we should disregard the FDA’s interpretation of Lohr as well as its unique qualification to determine whether its regulations and interpretation of the FDA statute (21 U.S.C. § 360k(a)) fulfill the purposes and objectives of Congress. In denying the import of the FDA’s position, which it has particularized in its Amicus Brief with respect to the Heart-Mate, the dissent has not given weight to the instruction furnished to us by the Supreme Court in Lohr.

That Court stated that "Congress has given the FDA a unique role in determining the scope of § 360k’s preemptive effect.” Lohr, 518 U.S. at 495-96, 116 S.Ct. 2240. Here, the FDA's position has been expressly authorized by the Solicitor General of the United States. Justice Breyer was prescient in acknowledging the FDA’s position when he wrote:

The ... FDA is fully responsible for administering the [Act]. That responsibility means informed agency involvement and, therefore, special understanding of the likely impact of both state and federal requirements, as well as an understanding of whether (or the extent to which) state requirements may interfere with federal objectives. The FDA can translate these understandings into particularized pre-emptive intentions accompanying its various rules and regulations. It can communicate those intentions, for example, through statements in regulations, preambles, interpretive statements, and responses to comments.

Id. at 505-06, 116 S.Ct. 2240 (Breyer, J., concurring in part) (internal citations and quotations omitted).

13 . This is the FDA's present opinion. See FDA Amicus Curiae Letter Br., Horn v. Thoratec Corp., 2004 WL 1143720 (3d Cir. May 11, 2004). It is consistent with the FDA’s statement of interest in Muiphree v. Pacesetter, Inc., in which it argued that PMA approval by the FDA “triggers preemption of a wide array of requirements imposed under state tort law.” See Statement of Interest in Support of Defendant Pacesetter’s Petition for Certification for Interlocutory Appeal of the United States of America at 5 & 7, Murphree v. Pacesetter, Inc. et al, No. 005429-00-3 (Tenn. Circuit Ct. Dec. 12, 2003).

14 . Horn does not allege that TCI failed to comply with the requirements imposed by the FDA when it approved the HeartMate. At oral argument, counsel for Horn twice stated that Horn was not making such an allegation. Tr. at 7:20-8:12 & 10:12-14.

15 . Pennsylvania's only medical device requirements which are specifically exempt from- preemption arise under the Pennsylvania Hearing Aid Sales Registration Law, 35 P.S. §§ 6700-504(4), 6700-506, 6700-507(2), see also 21 C.F.R. § 808.88.

16 .In her June 2004 Letter Brief at 10, Horn wrote: "In this case, Ms. Horn does not rely on any device-specific requirements."

17 . 21 C.F.R. § 808.1(d) provides:

State or local requirements are preempted only when the Food and Drug Administration has established specific counterpart regulations or there are other specific requirements applicable to a particular device under the act, thereby making any existing divergent State or local requirements applicable to the device different from, or in addition to, the specific Food and Drug Administration requirements ...

18 . This can be characterized as a "dual majority” case because Justice Breyer joined with the plurality on the result (i.e., no preemption), but joined with the dissent as to the rationale (i.e., a state common law claim can be preempted by § 3601c even though it was not specifically developed "with respect to” a particular medical device). See Note, The Precedential Value of Supreme Court Plurality Decisions, 80 Colum. L.Rev. 756, 767-69 (1980) (discussing dual majority cases).

19 . Horn emphasized in her June 2004 Letter Brief at 7 that "the claims in this case are based on state law claims of general applicability, not requirements specific to devices.”

20 . The Product Liability Advisory Council writes in its amicus curiae brief:

Even supposing one jury could provide manufacturers with proper incentives to make its products safer, what about every juiy? If the PMA process does not preempt state product liability suits [and general common law claims] imposing requirements at odds with the approved PMA, then juries in every state will influence device regulation, in numerous and often conflicting ways. See Brooks [v. Howmedica, Inc.], 273 F.3d at 797 ("The arguments advanced by Brooks ignore the need for national uniformity in product regulation, one of the explicit goals of the MDA.”) (citing H.R.Rep. No. 853,45 (1976)) ("If a substantial number of differing requirements applicable to a medical device are imposed by jurisdictions other than the Federal government, interstate commerce would be unduly burdened.”). Unless products liability claims [and general common law claims] such as plaintiff's are preempted, the FDA’s expert determinations will be supplanted by a myriad of common law regulators, each one less likely than the FDA to reach a right result.

21 . 21 C.F.R. § 814.80 provides that a device may not be manufactured, labeled, etc. in a manner inconsistent with any conditions to approval specified in the PMA approval order. TCI would have to submit a supplemental PMA application setting forth its proposed changes and seeking FDA approval of those changes. 21 C.F.R. § 814.3a(d). If the FDA were to reject TCI's application, TCI would be left in the untenable and unenviable position of having to comply with conflicting state and federal requirements; precisely the conflict the § 360k(a) preemption provision is meant to avoid.

22 . Similarly, Horn's claim respecting TCI's negligence in not furnishing a 'Dear Doctor' letter “warning that the heart pump shouldn't be installed if the sutures would face upward, toward the sternum,” Horn, June 2004 Letter Br. at 9, is preempted as it would either add to, or differ from, the federal requirement establishing the design of the HeartMate. See Mitchell v. Collagen Corp., 126 F.3d at 913-14 ("[T]o the extent that [the Mitchells' mislabeling, misbranding and adulteration] allega-sions claim that Collagen has incurred liability under state law despite its conformity to the requirements of the PMA, the state law claims must be considered preempted.”).

Insofar as Horn's claim is premised on the adequacies of the warnings reviewed and approved by the FDA in its PMA approval order, it is also preempted. See Martin, 105 F.3d at 1100 (“To allow a state cause of action for inadequate warnings would impose different requirements or requirements in addition to those required by federal regulations."). The PMA includes specimens of the labeling proposed to be used for the device, 21 U.S.C. § 360e(c)(l)(F), and this labeling must provide "adequate directions for use.” 21 U.S.C. § 352(f). Moreover, PMA approval expresses the FDA's determination that the proposed labeling meets the detailed labeling requirements set forth in its regulations. Any changes in the design, labeling or manufacturing processes that affect safety and effectiveness must receive FDA approval.

23 .FDA Amicus Curiae Letter Br. at 17-18.

24 . Martin v. Telectronics Pacing Sys., Inc., 105 F.3d 1090 (6th Cir.1997) ("Thus, because under the federal requirement the FDA has determined that the benefits of the device outweigh the risks and, under the state require-merit, a jury in a state court action could conclude that the risks outweigh the benefits, the state requirement is different from the federal requirement.”).

25 . See United States v. Mead Corp., 533 U.S. 218, 228, 121 S.Ct. 2164, 150 L.Ed.2d 292 (2001) ("The weight accorded to an administrative judgment in a particular case will depend upon the thoroughness evident in its consideration, the validity of its reasoning, its consistency with earlier and later pronouncements, and all those factors which give it power to persuade, if lacking power to control.'') (internal citations and quotations omitted).

26 . See Brooks v. Howmedica, Inc., 273 F.3d 785 (8th Cir.2001); Martin v. Medtronic, Inc., 254 F.3d 573 (5th Cir.2001); Kemp v. Medtronic, Inc., 231 F.3d 216 (6th cir.2000); Mitchell v. Collagen Corp., 126 F.3d 902, 913-14 (7th Cir.1997); Papike, 107 F.3d 737, 742 (9th Cir.1997).